The U.S. Supreme Court has upheld the most hotly disputed part of Arizona’s anti-immigrant law, S.B. 1070, which requires police to determine the immigration status of someone arrested or detained when there is “reasonable suspicion” they are not in the U.S. legally. The ACLU, along with a coalition of civil rights organizations, will continue to challenge the Arizona law on other constitutional grounds.

The ACLU will continue to fight back against anti-immigrant laws inspired by Arizona's notorious SB 1070 through impact litigation and legislative advocacy. Arizona's enactment of SB 1070 set off a number of copycat attempts in states across the country in 2011. There are now five states — Alabama, Georgia, Indiana, South Carolina and Utah — that have passed Arizona copycat laws.

The ACLU and other civil rights groups have filed lawsuits challenging all six laws. The Department of Justice has also filed lawsuits challenging Arizona, Alabama, South Carolina and Utah's anti-immigrant laws. Before the Supreme Court's ruling, federal courts blocked major provisions from taking effect in all six states.

Laws inspired by Arizona's SB 1070 invite rampant racial profiling against Latinos, Asian-Americans and others presumed to be "foreign" based on how they look or sound. They also authorize police to demand papers proving citizenship or immigration status from anyone they stop and suspect of being in the country unlawfully.